The English-born star, who shares 10-year-old Manon and Gulliver, nine, with McCrory, had adopted the American accent for his roles on "Homeland" and "Billions", and said that his wife now "has a horror" that he will transfer the intonation onto their children, reported Femalefirst.
"I don't do it (the accent) in front of them. They once spent a school term in the US and they started copying the accent in this comical, exaggerated way, elongating their vowels. I put a stop to that. My wife has a horror that the children will start talking American if we spend too much time out there," he said.
"I once did a US TV interview in my American accent and somehow it was seen by quite a few of my friends back in England.
"There were several irate text messages. 'You are British! Stop talking like an American!' It has become second nature to me now and I am happy to do it. That said, if I am with Brits I come out of it pretty quickly," Lewis told Mr Porter magazine.